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to come near (to); to approach
to be on the verge of; to be about to reach (a stage, period, etc.); to approach (e.g. a climax)
to overhang; to hang over
会議の雑談が終わりいよいよ本題に差し掛かるところだ。
We finally approach the main topic.
転職するか現職に留まるか人生の重要な岐路に差し掛かった。
I've come to a crossroads in life.
橋に差し掛かった時に雨が降った。
It rained when we approached the bridge.